Before I do activate any feature, are the current settings saved?

Solution

On the very first start of Tweak-XP, the software creates a System-Restore point. You may switch back to this point using the System-Restore feature of Windows XP. Please check the Windows XP documentation or help file for details on the System Restore feature.

Once you have set your system back to a system restore point prior the installation of Windows XP, all changes will be re-set.